WASHINGTON, April 22 (Xinhua) -- U.S. President Barack Obama's Asia tour, which kicked off Tuesday, is a bid to reinvigorate the administration's rebalancing to Asia, experts said.

"A presidential trip to the region reaffirms that the president takes this region very seriously," Kenneth Lieberthal, senior fellow at the Brookings Institution, told Xinhua in an interview.

Obama wants to "reinvigorate our engagement with Asia because he (sees), I think rightly, that it's the most important region in the world," Lieberthal added.

This view is in line with a recent statement from U.S. National Security Advisor Susan Rice, who said last week that U.S. security interests, core value promotion and trade interests are tied to Asia.

The trip includes stops in Japan, South Korea, the Philippines and Malaysia, with a differing focus for each country but an overarching U.S. goal of showing the region that it is still very much on the U.S. radar. A previous trip was canceled because of a government shutdown last October.

The Trans-Pacific Partnership (TPP) trade deal will be high on the agenda during Obama's visits to Japan and Malaysia.

However, Japanese and U.S. trade officials who continued last-minute efforts to reach agreement until Tuesday remained at loggerheads over a number of key issues.

Akira Amari, the Japanese minister in charge of TPP trade talks, said Tuesday that Japan and the United States may not announce a broad bilateral agreement trade pact during the summit talks between Obama and Japanese Prime Minister Shinzo Abe as "there is still a considerable distance."

Japanese Foreign Minister Fumio Kishida also said Monday that "what we expect to be the biggest outcome of the coming visit to Japan by President Obama is that the two leaders will show both at home and abroad that the Japan-U.S. alliance, which is vital for Japan's diplomacy, is undoubtedly unshakable and firm."

In Seoul, Obama will hold talks with South Korean President Park Geun-Hye that focus on ongoing tensions on the Korean Peninsula. The U.S. president will also attempt to ease tensions between Seoul and Tokyo.

Douglas Paal, Carnegie Endowment's Asia program director, has said China's steady pressure for a resumption of six-party talks is something that the Obama administration cannot keep resisting.

In the latest efforts of China to help de-escalate tensions on the Peninsula, Chinese President Xi Jinping held a phone conversation with President Park, in which Xi reiterates that China is firmly committed to realizing the denuclearization of the Korea Peninsula and encouraging the peaceful settlement of problems.

"China stands ready to keep close communication and coordination with South Korea on the peninsular issues, and hope all relevant parties can work together to easy tensions on the Peninsula and safeguard its peace and stability," Xi said.

Expressing her appreciation of China's constructive role, Park said Seoul is willing to keep communication and cooperation with Beijing.

All in all, amid allies' doubt about U.S. security commitments, Obama's trip "is the latest manifestation of the president's firm commitment to his policy of Asia Pacific rebalancing," Evan Medeiros, senior director for Asian affairs at the National Security Council, told a briefing Monday.

However, the U.S. engagement with some Asian countries will not be at China's expense and Washington is committed to building a new model of relationship with China by having more and better cooperation on the critical regional and global challenges, Medeiros said.

"Is (the president's trip) focused on containment of China? And the simple answer is no," he said.

WASHINGTON, April 22 (Xinhua) -- The United States is closely monitoring any possible "provocation" by the Democratic People's Republic of Korea (DPRK), the White House said Tuesday, as U.S. President Barack Obama embarked on a four-country tour of Asia.

"We are always mindful of the possibility that such an action could be taken," White House spokesman Jay Carney told reporters aboard Air Force One as Obama left for a week-long Asia trip, which would take him to Japan, South Korea, Malaysia and the Philippines. Full story

BEIJING, April 23 (Xinhua) -- Six months after a government shutdown forced him to scrap an Asia visit, U.S. President Barack Obama comes to the dynamic continent to consolidate Washington's engagement with the Asia-Pacific region.

The four-nation tour unfolds on the background of the Obama administration's so-called "rebalancing to Asia" policy, which features a U.S. commitment to shifting priorities and resources toward the other side of the Pacific Ocean. Full story